Theora Joiner is an easy-to-use tool to join multiple Theora files into one larger Theora file.
Theora Joiner is designed to join Theora files quickly without recompression or reduction in quality. Files must have identical parameters (such as frame size and frame rate) in order to be joined. (If you need to change frame size or frame rate, use oggResize)
Theora Joiner uses oggCat, a command-line utility from The Ogg Video Tools suite, developed by Bruno Brödner.
Theora Joiner requires Microsoft .NET 3.0. Windows Vista and Windows 7 have this pre-installed and most Windows XP users will have this installed.